Historically, women's sanitary protection products have been relatively unreliable in preventing staining of women's undergarments and outer garments during their menstrual periods. For example, large, bulky pads, which have high absorbency rates due to the use of hydrophilic materials such as wood pulp and rayon in their construction, nevertheless are often unable to retain absorbed mentrual fluid. They also tend to deform in use, leading to discomfort and the staining of undergarments and outer clothing. Even more recently developed, thinner pads, which contain polymer superabsorbent materials designed to aid in retaining fluid, have high failure rates. Furthermore, both types of pads tend to buckle and deform in an undesirable manner under pressure such that they cannot maintain contact with the perineal area. This distortion can create canals or paths along which menstrual fluid can flow without being absorbed, thereby causing staining as the fluid is channelled away from the absorbent. Although multiple longitudinal channels may be desired, most prior art pads merely buckle to create a few large voids, which is undesirable.
When resilient material is added to pads in order to prevent deformation, the pads become uncomfortable and extremely expensive to make. Further, bulky pads are not significantly more failure-proof than thinner pads.
It is, therefore, an object of this invention to provide an absorbent structure capable of quickly absorbing and retaining large quantities of body fluid.
It is another object of that invention to provide a sanitary napkin capable of absorbing menstrual fluid quickly and efficiently and retaining that fluid in the absorbent structure of the napkin so as to limit failure.
Yet another object of this invention is to provide a sanitary napkin which is flexible and conformable, yet resilient to bunching and twisting.
Additional objects of this invention will become evident in the ensuing description.